From 6d016c9c7f21a97249c4571e8d7265da1fd2f083 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Lukas=20Sandstr=C3=B6m?= Date: Tue, 20 Dec 2005 21:05:54 +0100 Subject: [PATCH] git-pack-redundant: speed and memory usage improvements MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Slab allocation of llist entries gives some speed improvements. Not computing the pack_list permutaions all at once reduces memory usage greatly on repositories with many packs. Signed-off-by: Lukas Sandström Signed-off-by: Junio C Hamano --- pack-redundant.c | 149 ++++++++++++++++++++++------------------------- 1 file changed, 69 insertions(+), 80 deletions(-) diff --git a/pack-redundant.c b/pack-redundant.c index 0a4327892..1869b38b7 100644 --- a/pack-redundant.c +++ b/pack-redundant.c @@ -8,6 +8,8 @@ #include "cache.h" +#define BLKSIZE 512 + static const char pack_redundant_usage[] = "git-pack-redundant [ --verbose ] [ --alt-odb ] < --all | <.pack filename> ...>"; @@ -33,29 +35,32 @@ static struct pack_list { struct pll { struct pll *next; struct pack_list *pl; - size_t pl_size; }; static struct llist_item *free_nodes = NULL; +static inline void llist_item_put(struct llist_item *item) +{ + item->next = free_nodes; + free_nodes = item; +} + static inline struct llist_item *llist_item_get() { struct llist_item *new; if ( free_nodes ) { new = free_nodes; free_nodes = free_nodes->next; - } else - new = xmalloc(sizeof(struct llist_item)); - + } else { + int i = 1; + new = xmalloc(sizeof(struct llist_item) * BLKSIZE); + for(;i < BLKSIZE; i++) { + llist_item_put(&new[i]); + } + } return new; } -static inline void llist_item_put(struct llist_item *item) -{ - item->next = free_nodes; - free_nodes = item; -} - static void llist_free(struct llist *list) { while((list->back = list->front)) { @@ -270,77 +275,58 @@ static void cmp_two_packs(struct pack_list *p1, struct pack_list *p2) } } -static void pll_insert(struct pll **pll, struct pll **hint_table) +void pll_free(struct pll *l) { - struct pll *prev; - int i = (*pll)->pl_size - 1; - - if (hint_table[i] == NULL) { - hint_table[i--] = *pll; - for (; i >= 0; --i) { - if (hint_table[i] != NULL) - break; + struct pll *old; + struct pack_list *opl; + + while (l) { + old = l; + while (l->pl) { + opl = l->pl; + l->pl = opl->next; + free(opl); } - if (hint_table[i] == NULL) /* no elements in list */ - die("Why did this happen?"); + l = l->next; + free(old); } - - prev = hint_table[i]; - while (prev->next && prev->next->pl_size < (*pll)->pl_size) - prev = prev->next; - - (*pll)->next = prev->next; - prev->next = *pll; } /* all the permutations have to be free()d at the same time, * since they refer to each other */ -static struct pll * get_all_permutations(struct pack_list *list) +static struct pll * get_permutations(struct pack_list *list, int n) { - struct pll *subset, *pll, *new_pll = NULL; /*silence warning*/ - static struct pll **hint = NULL; - if (hint == NULL) - hint = xcalloc(pack_list_size(list), sizeof(struct pll *)); - - if (list == NULL) + struct pll *subset, *ret = NULL, *new_pll = NULL, *pll; + + if (list == NULL || pack_list_size(list) < n || n == 0) return NULL; - if (list->next == NULL) { - new_pll = xmalloc(sizeof(struct pll)); - hint[0] = new_pll; - new_pll->next = NULL; - new_pll->pl = list; - new_pll->pl_size = 1; - return new_pll; + if (n == 1) { + while (list) { + new_pll = xmalloc(sizeof(pll)); + new_pll->pl = NULL; + pack_list_insert(&new_pll->pl, list); + new_pll->next = ret; + ret = new_pll; + list = list->next; + } + return ret; } - pll = subset = get_all_permutations(list->next); - while (pll) { - if (pll->pl->pack == list->pack) { - pll = pll->next; - continue; + while (list->next) { + subset = get_permutations(list->next, n - 1); + while (subset) { + new_pll = xmalloc(sizeof(pll)); + new_pll->pl = subset->pl; + pack_list_insert(&new_pll->pl, list); + new_pll->next = ret; + ret = new_pll; + subset = subset->next; } - new_pll = xmalloc(sizeof(struct pll)); - - new_pll->pl = xmalloc(sizeof(struct pack_list)); - memcpy(new_pll->pl, list, sizeof(struct pack_list)); - new_pll->pl->next = pll->pl; - new_pll->pl_size = pll->pl_size + 1; - - pll_insert(&new_pll, hint); - - pll = pll->next; - } - /* add ourself */ - new_pll = xmalloc(sizeof(struct pll)); - new_pll->pl = xmalloc(sizeof(struct pack_list)); - memcpy(new_pll->pl, list, sizeof(struct pack_list)); - new_pll->pl->next = NULL; - new_pll->pl_size = 1; - pll_insert(&new_pll, hint); - - return hint[0]; + list = list->next; + } + return ret; } static int is_superset(struct pack_list *pl, struct llist *list) @@ -428,6 +414,7 @@ static void minimize(struct pack_list **min) struct pll *perm, *perm_all, *perm_ok = NULL, *new_perm; struct llist *missing; size_t min_perm_size = (size_t)-1, perm_size; + int n; pl = local_packs; while (pl) { @@ -441,8 +428,7 @@ static void minimize(struct pack_list **min) missing = llist_copy(all_objects); pl = unique; while (pl) { - llist_sorted_difference_inplace(missing, - pl->all_objects); + llist_sorted_difference_inplace(missing, pl->all_objects); pl = pl->next; } @@ -453,19 +439,21 @@ static void minimize(struct pack_list **min) } /* find the permutations which contain all missing objects */ - perm_all = perm = get_all_permutations(non_unique); - while (perm) { - if (perm_ok && perm->pl_size > perm_ok->pl_size) - break; /* ignore all larger permutations */ - if (is_superset(perm->pl, missing)) { - new_perm = xmalloc(sizeof(struct pll)); - memcpy(new_perm, perm, sizeof(struct pll)); - new_perm->next = perm_ok; - perm_ok = new_perm; + for (n = 1; n <= pack_list_size(non_unique) && !perm_ok; n++) { + perm_all = perm = get_permutations(non_unique, n); + while (perm) { + if (is_superset(perm->pl, missing)) { + new_perm = xmalloc(sizeof(struct pll)); + memcpy(new_perm, perm, sizeof(struct pll)); + new_perm->next = perm_ok; + perm_ok = new_perm; + } + perm = perm->next; } - perm = perm->next; + if (perm_ok) + break; + pll_free(perm_all); } - if (perm_ok == NULL) die("Internal error: No complete sets found!\n"); @@ -537,6 +525,7 @@ static void scan_alt_odb_packs(void) alt->all_objects); local = local->next; } + llist_sorted_difference_inplace(all_objects, alt->all_objects); alt = alt->next; } } -- 2.30.2